Submission #1182691

#	Time	Username	Problem	Language	Result	Execution time	Memory
1182691		Dedibeat	Construction Project 2 (JOI24_ho_t2)	C++20	45 / 100	2096 ms	18872 KiB

Main

#include<bits/stdc++.h>
using namespace std;
using ll = long long;

#define F first
#define S second 
#define all(x) (x).begin(), (x).end()

template<typename T, typename U>
ostream &operator<<(ostream &os, const pair<T, U> &p)
{
    return os << "(" << p.F << "," << p.S << ")";
}
template<typename T>
void print(const T &v, int lim = 1e9)
{
    for(auto x : v) 
        if(lim-- > 0) cout << x << " ";
    cout << "\n";
}
#define int long long
int N, M, S, T, L, K;
using node = pair<ll, ll>;
vector<node> adj[200005];
signed main()
{
    ios::sync_with_stdio(0); cin.tie(NULL); cout.tie(NULL);
    cin >> N >> M >> S >> T >> L >> K;
    for(int i = 0; i < M; i++)
    {
        int u, v, w;
        cin >> u >> v >> w;
        adj[u].emplace_back(v, w);
        adj[v].emplace_back(u, w);
    }

    auto dij = [&](int start)
    {
        priority_queue<node, vector<node> , greater<node>> q;
        vector<ll> d(N + 5, 1e17);
        d[start] = 0;
        q.emplace(0, start);
        while(!q.empty())
        {
            auto [c, v] = q.top(); q.pop();
            if(c != d[v]) continue;
            for(auto [u, w] : adj[v])
            {
                if(c + w < d[u])
                {
                    d[u] = c + w;
                    q.emplace(c + w, u);
                }
            }
        }
        return d;
    };


    auto ds = dij(S);
    auto dt = dij(T);

  //  print(ds);
  //  print(dt);

    ll cnt = 0;
    for(int i = 1; i <= N; i++)
    {
        for(int j = i + 1; j <= N; j++)
        {
            ll cost = min(ds[i] + dt[j], ds[j] + dt[i]) + L;
            if(cost <= K)
            {
                cnt++;
            //   cout << cost << endl;
             //   cout << i << " ," << j << endl;
            }
        }
    }

    if(ds[T] <= K) cnt = N * (N - 1) / 2;

    cout << cnt << "\n";

    
}

• Subtask 1: 0 / 8
• Subtask 2: 16 / 16
• Subtask 3: 29 / 29
• Subtask 4: 0 / 47